Question 218361
One number is seven more than twice another. If their sum is decreased by nine, the result is thirteen. Find the numbers.


Step 1.  Let x be one number


Step 2.  Let 2x be twice the number x


Step 3.  Let 2x+7 be the other number since it's seven more than twice another.


Step 4  Let x+2x+7  be the sum.


Step 5.  Let x+2x+7-9=13 since their sum is decreased by nine and the result is thirteen.


Step 6.  Solving yields the following steps:


{{{x+2x+7-9=13}}}


{{{3x-2=13}}}


Add 2 to both sides


{{{3x-2+2=13+2}}}


{{{3x=15}}}


Divide by 3 to both sides of the equation


{{{3x/3=15/3}}}


{{{x=5}}} then {{{2x+7=17}}}


Check if sum is decreased by 9 to yield 13:  5+17-9=13...which is true statement.


Step 7.  ANSWER:  The numbers are 5 and 17.


I hope the above steps were helpful.


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And good luck in your studies!


Respectfully,
Dr J

http://www.FreedomUniversity.TV